U.S. Pat. Nos. 4,264,362, 4,522,190 and 5,611,329 describe embodiments of Flameless Ration Heaters (FRHs) of the type employed by the U.S. military to heat individual field rations (known as a “Meal Ready to Eat (MRE)). The heat source for such heaters is a mixture of an Mg—Fe alloy, NaCl, antifoaming agents and an inert filler. Upon exposure to water, the alloy under goes an exothermic reaction, that is, oxidation of the magnesium component of the alloy and generates heat.
The FRH is typically packaged in a sealed polyethylene envelope. In use the envelope is opened, a food retort pouch is inserted into the envelope and water is added to the envelope to contact the FRH for generating heat.
However, the oxidation of magnesium generates hydrogen gas, which may pose a safety hazard during storage and/or use of the FRH.
It would be useful to overcome the shortcomings of the prior art in order to provide a heating apparatus that provides a high heat output, in a controlled and reliable manner, that is resistant to environmental moisture and provides good storage stability and that does not generate a safety hazard during storage, shipping, use, or disposal and provides good storage stability and that does not generate a safety hazard during storage, shipping, use, or disposal.